images and sound Flashcards
how are images stored
as a series of pixels
definition of pixels
tiny dots that make up a bitmap
pixel is short for…
picture element
what is a colour depth
number of bits used for each pixel
image resolution formula
width x height = bitmap image in pixels
how to work out number of bits an image will use
file size in bits =
image size x. colour depth =
width x height x colour depth
number of colour made by colour depth formula
2 to the power of n
n is the number of bits per pixel
sound is recorded by a microphone as an … signal
analogue
which is a piece of continually changing data
what is sampling
process of converting analogue sound to digital data
what is a sample à measure of
amplitude and a point in time
what is the sample rate
how many samples you can take in a second
in hertz
common sample rate is 44.1 kHz
what is sample resolution
samples taken each second
size of à sound file formula
file size in bits=
sample rate x sample resolution x length (in seconds)
